___________________________________________________________________________________________
Technical Specification for
11kv Packaged substation
(
with 990/630/400KVA oil / dry type transformers
)Specification no –BSES-SP-EPSX-01-R2
Prepared by: Reviewed by Approved by: Rev Date
Tarun D Sharma D Sharma
___________________________________________________________________________________________ Index
1.0 Scope of supply...3
2.0 Applicable codes & standards ...3
3.0 Purchaser electrical system data ...4
4.0 11kv packaged substation configuration & enclosure ...4
5.0 11kv Ring Main Unit (RMU)...4
6.0 11kv XLPE Cable & termination kit ...9
7.0 Distribution oil transformer (990KVA / 630 KVA / 400KVA Sealed type) ...10
8.0 Dry Type Distribution Transformer (400 / 630 / 1000 KVA)...17
9.0 Low voltage Bus bar system ...26
10.0 Low voltage switchgear, ACB & MCCB...26
11.0 Automatic Power Factor Correction system ...27
12.0 Energy metering - LT...29
13.0 Enclosure for packaged substation ...30
14.0 Earthing & Illumination ...31
15.0 Labels & painting...32
16.0 Approved make list of major equipments. ...32
17.0 Quality assurance by Vendor ...33
18.0 Inspection & testing ...33
19.0 Shipping, Handling and Site support ...33
20.0 Deviations...34
Annexure - A Scope of supply ...35
Annexure - B Technical particulars (Data by purchaser) ...37
___________________________________________________________________________________________ Technical specification for 11kv Packaged Substation
1.0 Scope of supply
For scope of supply, refer annexure A & for minimum bill of material refer Annexure E 2.0 Applicable codes & standards
Materials, equipment and methods used in the manufacture of 11kv Packaged substation shall conform to the latest edition of all applicable parts of following codes & standards including amendments –
Indian electricity act & Indian Electricity Rules CBIP manual on transformers
IEC 60076 Power transformers
IEC 60694 Specification for high voltage switchgear
IEC 60439-1 Low voltage switchgear & control gear assemblies IEC 60529 Degree of enclosures provided by enclosures IEC 60664-1 Insulation coordination for low voltage systems
IEC 62262 Degree of protection provided by enclosure against mechanical shocks
IEC 62271-202 High voltage switchgear & control gear - prefabricated substation IEC 60044 Instrument transformers - Current & voltage transformers
IEC 60225 Electrical relays IEC 60625 High voltage switches IEC 60502 Power cables
IEC 60947-2 Low-voltage switchgear and control gear : Circuit-breakers IS 2026 Power transformers
IS 11171 Dry type transformers
IS 6600 Loading of power transformers
IS 13947 Low voltage switchgear & control gear IS 2099 Bushings for voltages above 1000v IS 3156 Voltage transformers
IS 2705 Current transformers
IS 1554 PVC cables
IS 7098 XLPE cables
IS 2629 Recommended Practice for Hot-Dip Galvanizing of Iron and Steel IS 4759 Hot-dip zinc coatings on structural steel and other allied products IS 13585 Shunt capacitors
IS 13340 Shunt capacitors
IS 3043 Code of practice for Earthing IS 335 Insulating oils
IS 8130 Conductors for insulated cables
IS 5 Ready mixed paints
IS:13703 HRC Fuse
In the event of direct conflict between various order documents, the precedence of authority of documents shall be as follows -
___________________________________________________________________________________________ ii. Specification including applicable codes, standards
iii. Approved Vendor Drawings iv. Other documents
3.0 Purchaser electrical system data
3.1.0 HT supply system 3 phase AC, 3 wire
3.1.1 Rated voltage 11kv +/-10%
3.1.2 Rated frequency 50 Hz ± 5%
3.1.3 Fault level 350MVA – 18.5kA
3.2.0 LT supply system 3 phase AC, 4 wire
3.2.1 Rated voltage 415v +/-10%
3.2.2 Rated frequency 50 Hz ± 5%
3.2.3 Fault level 35MVA – 50kA
4.0 11kv packaged substation configuration & enclosure
The packaged substation shall have all the following major components in addition to the other items required for satisfactory performance of equipment –
4.1 Metallic painted enclosure with steel base frame for overall package
4.2 11kv Ring main unit 3 way (2 no Load break switches + 1 no circuit breaker) 4.3 11kv XLPE armored Aluminum cable with termination kit
4.4 990KVA / 630 KVA / 400KVA, 11kv/0.433volt, Dyn11 oil type sealed / dry type transformer with all accessories
4.5 Low voltage bus bar system with epoxy insulators
4.6 Low voltage 2000Amp / 1250A / 800A ACB for incoming with 7 / 5 nos. 400A MCCB for outgoing feeder.
4.7 300kVAR / 200KVAR APFC system with control relay & 630A / 400A Amp incomer MCCB.
4.8 Energy meter box at transformer LT side including CTs 1600 / 5 amp
4.9 Supply of RTU with 48/24V battery set in LT compartment for automation. Refer specification of Automation.
4.10 Substation internal cabling, lighting & earthing system along with required hardware, gaskets, gland plates etc
5.0 11kv Ring Main Unit (RMU)
The equipment shall have all the following features –
5.1.0 RMU Configuration
5.1.1 RMU Configuration Two Load break switches (LBS) + one transformer circuit breaker (TCB). Both LBS shall be electrically operated.
___________________________________________________________________________________________ 5.1.3 Load break switch, Circuit breaker
& earth switch in RMU panel
All shall be non draw out type, fixed position
5.1.4.1 Insulation medium for panel SF6 gas or Dry air in sealed metallic tank
5.1.4.2 breakers & load break switches
SF6 gas or Vacuum type (with dis connector & earth switch)
5.1.5 Arc interruption chamber for breaker
Arc interruption chamber of breakers shall be separate from the main insulated tank. (Desirable feature) 5.1.6 Maximum dimensions for a 3 way
panel (1 CB + 2 LBS)
1250 W x 800 D x 2000 H
5.2.0 RMU panel construction
5.2.1 RMU Panel type Metal enclosed, framed,
Compartmentalized panel construction
5.2.2 Service location Indoor, non air conditioned
environment
5.2.3 Mounting Free Standing
5.2.4 Overall enclosure protection IP4X minimum, vermin proof
5.2.5 Doors Front access with anti theft hinge
Covers Bolted for rear access, with handles
5.2.6
All the accessible bolts / screws shall be vandal proof. One set of required
Special tools per RMU (if any) shall be in the scope of supply.
5.2.7 Construction Sheet metal 2.5mm thick CRCA
5.2.8.1 Base frame made of steel for RMU Raised frame of 300 mm height 5.2.8.2 Foundation bolts + Fixing bolt for
RMU & frame (in case the frame is supplied loose)
Cable box compartment should be extended up-to base-frame bottom to have metallic separation between each of the feeders at base frame level too. Painting should match with RMU shade.
5.2.9 Lifting lugs Four numbers
5.2.10 Cable entry Bottom
5.2.11 Gland plate 3mm metallic, removable type & split type in two parts,
5.2.12 Cable type & size 3c x 120 or 300 sq mm 11000v grade Al conductor XLPE/ PILC with armor & PVC outer sheath
5.2.13.1 Terminals for 11kv cable termination
with right angled boots, set of required size of Brass Nut bolt & Bimetallic washers.
5.2.13.2 Termination type suitable for heat shrinkable type 5.2.13.3 Termination height from gland plate 700mm minimum
5.2.14 Bus bar Tinned copper with sleeve (Sizing
Calculation to be submitted in support of its Guaranteed S.C. rating / Capability)
5.2.14.1 Bus bar continuous rated current 630 Amp (at designed 40 deg.C ambient)
___________________________________________________________________________________________ 5.2.14.2 Bus bar short time withstand
capacity
18.5 KA for 3 sec 5.2.14.3 Bus bar support insulator material SMC / DMC resin 5.2.14.4 Maximum temperature rise above
reference ambient 40 deg C
In line with Table 3 of IEC694
5.2.15.0 Earth bus bar Aluminum / Copper sized for rated fault duty for 3 sec
5.2.15.1 Earth bus internal connection to all non current carrying metal parts
By 2.5 sq mm copper flexible wire, Earth connection point maximum 1 meter away from cable test facility 5.2.15.2 Earth bus external connection to
owners earth
Studs on both sides with holes for M10 bolt + hardware to readily receive purchaser earth connection
5.2.16 Cooling arrangement By natural air without fan
5.2.17 Panel internal wiring Stranded flexible color coded PVC insulated copper wire 2.5 sq mm, 1100 volt grade (AC- black, DC – grey, Earth – green)
5.2.18 Hardware (Nut, bolts & handle) Stainless steel (Except termination nut-bolts which are Brass / Tinned Copper)
5.2.19 Gasket Neoprene rubber
5.2.20 Marshalling terminal blocks 2.5 Sq mm, Nylon 66 material, screw type + 20% spare in each row of TB. 5.2.21 Panel cover fixing bolts Allen head 6mm with hexagonal slot 5.2.22 Padlock facility Required for all earth switches & all
handles 5.2.24 Explosion vents
To ensure operator’s safety, design should ensure that gases / flames generated during flash over / blast in any of the compartment, must not come out from the front of RMU. Internal arc test report (for Cable compartment & other compartments) must be submitted to support above along with RMU GA drawing indicating these vents.
5.3.0 Load break switch (Isolator)
5.3.1 Type Three poles operated
simultaneously by a common shaft 5.3.2 Arc interruption in dielectric medium SF6 or vacuum
5.3.3.1 Operating mechanism for close / open
Electrically operated with motor mechanism.
5.3.3.2 Addition / removal of motor Without overhaul of operating mechanism
5.3.3.3 Manual operation Possible without removal of motor 5.3.3.4 RMU without motor complete with power & control wiring
so that only motor can be added at later date
5.3.4.1 Motor rated voltage 24v DC / 48v DC 5.3.5 Continuous rating of LBS at design
ambient
630 Amp
5.3.6 Short time withstand capacity 18.5 KA for 3 sec 5.3.7 Fault making capacity 46.3 KA peak
___________________________________________________________________________________________ 5.3.8 Minimum number of operations at
rated current (as per IEC 60265)
To be guaranteed by manufacturer, test certificate from authorized test laboratory to be submitted
5.3.9 Minimum number of operations at rated fault current (as per IEC 60265)
Same as above
5.3.10 Fault passage indicator (FPI) To be provided on right hand side of one LBS for panel type 1CB + 2 LBS
5.4.0 Circuit breaker Transformer circuit breaker - TCB
5.4.1 Type Three pole, operated simultaneously
by a common shaft 5.4.2 Arc interruption in dielectric medium SF6 gas or Vacuum
5.4.3 Operating mechanism - TCB Manual spring charged stored energy type
5.4.4 Emergency trip / open push button On panel front
5.4.5.1 Continuous rating 630 Amp at ambient design 40deg C 5.4.5.2 Short time withstand capacity 18.5 KA for 3 sec
5.4.6 Minimum number of operations at rated current (as per IEC 62271)
To be guaranteed by manufacturer, test certificate from authorized test laboratory to be submitted
5.4.7 Fault making capacity 46.3 KA peak 5.4.8 Fault breaking capacity 18.5 KA Minimum 5.4.9 Minimum number of operations at
rated Fault current (as per IEC 62271)
To be guaranteed by manufacturer, test certificate from authorized test laboratory to be submitted
5.4.10 Breaker status auxiliary contact 2NO + 2NC wired to terminal block 5.4.11 Current transformer ratio 80-150 / 1 amp
Considering three core cable terminations, mounting flexibility must be there for CT’s (in horizontal & vertical direction both). Additionally, some CAUTION marking (by sticker/ paint) should be there to avoid CT’s installation above the screen of cable (i.e. earth potential point.)
5.4.12 CT accuracy class 10P10 minimum
5.4.13 Protection relay Self powered, Microprocessor based Numerical relay (LCD display is desirable), IDMT over current / earth fault protection with high set element, manual reset type
5.4.14 Relay aux contacts for remote indication
Potential free, 1NO+1NC wired to TB
5.4.15 Shunt trip 230v AC (for WTI trip & door limit switch of enclosure or transformer)
To be wired to terminal blocks
5.5.0 Earth switch
5.5.1 Type for each Load break switch. Three Pole, operated simultaneously by a common shaft
5.5.2 Switching in dielectric medium Dry Air in sealed medium or SF6 gas 5.5.3 Operating mechanism for close &
open
Manual
5.5.4 Fault making capacity 50 kA (Desirable)
___________________________________________________________________________________________ 5.5.6 Disconnect switch (if provided in
series with vacuum bottle)
Desirable to be located on purchaser cable connection side of vacuum bottle
5.6.0 Requirements of sealed housing live parts (RMU SF6 gas chamber)
5.6.1 Enclosure Stainless steel enclosure, IP67 class
5.6.2 SF6 gas pressure low alarm To be given
5.6.3 Provision for SF6 gas filling To be given (For ‘sealed for life’ design of RMU, this is not applicable)
5.6.4 Provision for SF6 gas pressure indication
Manometer with non return valve 5.6.5 Arc interruption method for SF6
breaker / Load break switch
Puffer type / rotating arc type 5.6.6 Potential free contacts for SF6 gas
pressure low
1NO +1NC (Desirable) 5.7.0 RMU operation interlocks
5.7.1.1 Interlock type Mechanical
5.7.1.2 Load break switch & respective earth switch
Only one in ‘close’ condition at a time
5.7.1.3 Circuit breaker & respective earth switch
Only one in ‘close’ condition at a time
5.7.2 Prevent the removal of respective cable covers if load break switch or circuit breaker is ‘ON’
Electrical / Mechanical
5.7.3 Prevent the closure of load break switch or circuit breaker if respective cable cover is open
Electrical / Mechanical
5.7.4 Cable test plug for LBS/CB accessible only if Earth switch connected to earth
Mechanical
5.8.0 Indications & signals For SCADA & Local 5.8.1 Operation counter on front / Inside
the RMU LT chamber
To be provided for each LBS & Circuit breaker, with minimum four digits & non- re-settable type
5.8.2 Cable charge status indication for all LBS & CB
capacitor type voltage indicators with LED on all the phases (Shall be clearly visible in day light)
5.8.3 Spring charge status indication On front for breaker 5.8.4 Earth switch closed indication (For
Each LBS)
On front 5.8.5 Load break switch ON/OFF
indication
Green for OFF / Red for ON 5.8.6 Circuit breaker On/OFF indication Green for OFF / Red for ON 5.8.7 Circuit breaker protection relay
operated on fault
Flag 5.8.8 Fault passage indication on LBS Flag 5.8.9 Status signals to SCADA - to be
wired to marshalling terminal block
2NO + 2NC
5.8.9.1 LBS close / open potential free contacts 5.8.9.2 LBS & CB Earth Switch close /open potential free contacts
___________________________________________________________________________________________ 5.8.9.3 Battery charger Fail potential free contacts
5.8.9.4 CB close / open potential free contacts 5.8.9.5 Protection relay operated potential free contacts
5.8.9.6 FPI operated potential free contacts
5.8.9.7 SF6 gas pressure low potential free contacts) 5.8.10.1 Commands from SCADA - to be
wired to marshalling terminal block
LBS close / open. Other details please see automation philosophy.
5.8.10.2 FPI Reset
5.9.0 Mimic diagram, labels & finish On panel front with description of function & direction of operation of handles/buttons
5.9.1 Mimic diagram (Shall not be preferred with Stickers)
Operating instruction chart and Do’s & Don’ts in Hindi / local language to be displayed on left / front side of panel enclosure on Al Sheet, duly affixed on panel.
5.9.2 Name plate on panel front Fixing by rivet only
5.9.2..1 Material Anodized aluminum 16SWG / SS
5.9.2.2 Background SATIN SILVER
5.9.2.3 Letters, diagram & border Black
5.9.2.4 Process Etching
5.9.2.5 Name plate details Month & year of manufacture, equipment type, input & output rating, purchaser name & order number, guarantee period
5.9.3 Labels for meters & indications Anodized aluminum with white character on black background OR 3 ply lamicoid
5.9.4 Danger plate on front & rear side Anodized aluminum with white letters on red background
5.9.5 Painting surface preparation Shot blasting or chemical 7 tank process
5.9.6 Painting external finish Powder coated epoxy polyester base grade A, shade - RAL 7032, uniform thickness 80 micron minimum
5.9.7 Painting internal finish Powder coated epoxy polyester base grade A, shade - white, uniform thickness 80 micron minimum
6.0 11kv XLPE Cable & termination kit
The 11kv XLPE cable connection from RMU to distribution transformer shall be conforming to IS 7098 and shall have all the following features -
6.1 Cable type & size XLPE insulated armored cable 3c150sqmm Aluminum conductor
6.2 Cable voltage grade 11kv
6.3 XLPE insulation thickness 3.14 mm minimum
___________________________________________________________________________________________ 6.5 Insulation screen With semi conducting extrusion, copper
tape & water swellable tape
6.6 Type of armor GI flat as per table 4 of 7098 part 2 6.7 11kv cable termination at RMU &
Distribution transformer
By 11kv grade termination kit, heat shrink type
6.8 Cable support from RMU to
transformer HT side cable box
GI cable tray 300mm wide
7.0 Distribution oil transformer (990KVA / 630 KVA / 400KVA Sealed type) The distribution transformer shall be designed to comply with following features –
7.1.0 Major Design criteria
7.1.1.1 Voltage variation on supply side + / - 10 % 7.1.1.2 Frequency variation on supply side +/ - 5 % 7.1.1.3 Combined variation of voltage and
frequency
- 20 % or + 10 %
7.1.1.4 Service Condition Refer Annexure B
7.1.1.5 Insulation level
One minute power frequency withstand voltage
3kv for 415v system & 28kv for 11kv system Lightning impulse withstand voltage 75kv peak for 11kv system 7.1.1.6 Short Circuit withstand level
Three phase dead short circuit at secondary terminal with rated voltage maintained on the other side
For 3 sec for 990KVA / 630 KVA / 400KVA transformer with 5 % impedance
7.1.1.7 Overload capability As per IS 6600
7.1.1.8 Noise level Shall not exceed limits as per
NEMA TR-1 with all accessories running measured as per IEC 551 / NEMA standard
7.1.1.9 Radio Influence Voltage Maximum 250 microvolt 7.1.1.10 Harmonic currents Transformer to be designed for
suppression of 3rd, 5th, 7th harmonic voltages and high frequency
disturbances.
7.1.1.11 Partial Discharges Transformer to be free from partial discharge up to 120 % of rated voltage as the voltage is reduced from 150 % of rated voltage i.e. there shall be no significant rise above background level
7.1.2 Major Parameters
7.1.2.1 Rating 990KVA / 630 KVA / 400 KVA
7.1.2.2 Voltage Ratio 11kv / 433 volts
7.1.2.3 Vector Group Dyn11
7.1.2.4 Impedance at 75 deg C 5%, tolerance as per IS
7.1.2.5 Losses at 75 deg C With ONAN cooling
7.1.2.5.1 No load Loss
___________________________________________________________________________________________
b) For 630 KVA 1.0 Kw Max.
c) For 990 KVA 1.4 Kw Max.
7.1.2.5.2 Load losses at principal tap
a) For 400 KVA 5.1 Kw max
b) For 630 KVA 6.8 Kw max.
c) For 990 KVA 10.8 Kw Max.
7.1.2.6 Temperature Rise top oil – without enclosure
30 Deg C max over ambient 40 Deg C
7.1.2.7 Temperature Rise winding – without enclosure
40 Deg C max over ambient 40 Deg C
7.1.2.8 Flux density 1.7 Tesla at 100% rated voltage
1.9 Tesla at 110% rated voltage 7.1.2.9 Current density 3 amp / sqmm for HV & LV winding 7.1.2.10 Tapping on HV winding Off circuit +/- 5% in 2.5% step
Design Clearances Phase - phase Phase - earth
11kv system 180mm 120mm
7.1.2.11
415v system 25mm 25mm
7.2.0 Transformer construction
7.2.1 Type Double Copper wound, three
phase, oil immersed, with ONAN cooling
7.2.2.1 Tank Type tested design
7.2.2.1.1 Type Sealed type, Hermetic sealing
7.2.2.1.2 Material of Construction Mild steel plate with low carbon
7.2.2.1.3 Plate Thickness To meet the requirements of
pressure and vacuum type tests as per CBIP manual
7.2.2.1.4 Welding features
i) All seams and joints shall be double welded
ii) All welding shall be stress relieved for sheet thickness greater than 35 mm
iii) All pipes, stiffeners, welded to the tank shall be welded externally iv) All corrugated fins or expansion bellows provided shall be double welded.
7.2.2.1.5 Tank features
i) Bottom with stiffeners & adequate space for collection of sediments ii) No external pocket in which water can lodge
iii) Tank bottom with welded skid base
i) Strength to prevent permanent deformation during lifting, jacking, transportation with oil filled.
v) Minimum disconnection of pipe work and accessories for cover lifting vi) Tank to be designed for oil filling under vacuum
vii) tank cover fitted with lifting lug 7.2.2.3 Inspection cover for bushing & Core
/ Wind
As per manufacturer standard 7.2.2.4 Fittings and accessories on main
tank
As per clause 7.3.0 7.2.2.5 Core
___________________________________________________________________________________________
7.2.2.5.1 Material High grade , non ageing, low loss,
high permeability, grain oriented, cold rolled silicon steel lamination
7.2.2.5.2 Grade Minimum M4, thickness not more
than 0.27mm. 7.2.2.5.3 Core Design Features
i) Magnetic circuit designed to avoid short circuit paths within core or to the earthed clamping structures
ii) Magnetic circuit shall not produce flux components at right angles to the plane of lamination to avoid local heating
iii) Least possible air gap and rigid clamping for minimum core loss and noise generation
iv) Adequately braced to withstand bolted faults on secondary terminals without mechanical damage and damage/ displacement during transportation and positioning
v) Percentage harmonic potential with the maximum flux density under any condition limited to avoid capacitor overloading in the system
vi) All steel sections used for supporting the core shall be thoroughly sand blasted after cutting , drilling, welding
vii) Provision of lifting lugs for core coil assembly
viii) Supporting framework designed not to obstruct complete drainage of oil from transformer
7.2.2.6 Winding
7.2.2.6.1 Material Electrolytic Copper
7.2.2.6.2 Maximum Current Density allowed Maximum 3 amp / sqmm
7.2.2.6.3 Winding Insulating material Class A, non catalytic, inert to transformer oil, free from compounds liable to ooze out, shrink or collapse. Super enamel insulation is not accepted.
7.2.2.6.4 Winding Insulation Uniform
7.2.2.6.5 Design features
i) Stacks of winding to receive adequate shrinkage treatment
ii) Connections braced to withstand shock during transport, switching, short circuit, or other transients.
iii) Minimum out of balance force in the winding at all voltage ratios. iv) Conductor width on edge exceeding six times its thickness v) Transposed at sufficient intervals
vi) Coil assembly shall be suitably supported between adjacent sections by insulating spacers + barriers
vii) Winding leads rigidly supported , using guide tubes if practicable viii) Winding structure & insulation not to obstruct free flow of oil through ducts
7.2.2.7.1 Transformer Oil as per IS 335 and purchaser’s
specification.
Class 1 new mineral insulating oil, shall be certified not to contain PCBs. Naphthalene base with anti oxidant inhibitor subject to Purchaser’s specification SP-EBOO-01-R0.
7.2.2.8 Bushings and Terminations
___________________________________________________________________________________________ voltage class and creepage 25mm/kv
7.2.2.8.2 Type of LV side bushing Indoor, Epoxy resin cast, 1kv voltage class and creepage 25mm/kv
7.2.2.8.2. 1
Essential provision for LV side line bushing
It shall be complete with copper palm suitable for tinned copper busbar of size 100x12 mm
7.2.2.8.2. 2
Essential provision for LV side neutral bushing
In case of neutral bushing the stem and bus bar palm shall be integral without bolted, threaded, brazed joints. Bus bar size shall be 100x12 mm
7.2.2.8.3 Arcing Horns Not required
7.2.2.8.4 Support insulators inside HV cable box if provided
Epoxy resin cast, 12kv rated voltage
7.2.2.8.5 Termination on HV side bushing Cable connection through cable box with disconnecting link
7.2.2.8.6 Termination of LV side bushing Bus bar connection 7.2.2.8.7 Minimum creepage distance of all
bushings and support insulators.
25mm/kv
7.2.2.8.8 Protected creepage distance At least 50 % of total creepage distance
7.2.2.8.9 Continuous Current rating Minimum 20 % higher than the current corresponding to the minimum tap of the transformer 7.2.2.8.1
0
Rated thermal short time current 26.3kA for 3 sec 7.2.2.8.1
1
Atmospheric protection for clamp and fitting of iron and steel
Hot dip galvanizing as per IS 2633 7.2.2.8.1
2
Bushing terminal lugs in oil and air Tinned copper 7.2.2.8.1
3
Sealing washers /Gasket ring Nitrile rubber/ Expanded TEFLON(PTFE) as applicable 7.2.2.9 Current Transformers
7.2.2.9.1 Provision On all three phases on LV side
7.2.2.9.2 Mounting On LV side bushings on all three
phases with the help of fibre glass mounting plate affixed to main tank by nut bolt arrangement
7.2.2.9.3 Maintenance requirements Replacement should be possible by removing fixing nut of mounting plate without disturbing LT bushing 7.2.2.9.4 Accuracy Class & ISF 0.5 / 10
7.2.2.9.5 Burden 15 VA
7.2.2.9.6 Type Resin Cast Ring type suitable for
outdoor use
7.2.2.9.7 CT ratio 1600/5 amp
7.2.2.10 Off Circuit tap Switch on HV winding
___________________________________________________________________________________________ 1
7.2.2.10. 2
Type Rotary type, 3 pole gang operated,
7.2.2.10. 3
Operating Voltage 11kv
7.2.2.10. 4
Rated Current for tap Switch
a) For 400 KVA 60 Amps
b) For 630 & 990 KVA 100 Amps 7.2.2.10.
5
Operating Handle External at suitable height to be operated from ground level.
7.2.2.10. 6
Tap position indicator With direction changing facility, locking arrangement, caution plate metallic fixed by rivet.
7.2.2.11 Pressure Relief Device required 7.2.3 Hardware
7.2.3.1 External Stainless Steel
7.2.3.2 Internal Cadmium plated except special
hardware for frame parts and core assembly as per manufacturer’s design
7.2.4 Gasket
7.2.4.1 For Transformer , surfaces interfacing with oil like inspection cover etc.
Nitrile rubber based / cork
7.2.4.2 For Cable boxes, Marshalling box, etc.
Neoprene rubber 7.2.5 Valves
7.2.5.1 Material of construction Brass / gun metal
7.2.5.2 Type Both end flanged gate valve /
butterfly valve depending on application
7.2.5.3 Size As per manufacturer’s standard
7.2.5.4 Essential provision Position indicator, locking rod, padlocking facility, valve guard, cover plate.
7.2.6 Cable routing on Transformer Control cables for accessories on transformer tank shall be routed through perforated GI trays
7.2.6.1 Specification of wires to be used inside marshalling box , OLTC drive mechanism
PVC insulated multi-strand flexible copper wires of minimum 2.5 sq mm size, 1100 V grade as per latest edition of relevant IS
7.2.7 Terminal Blocks to be used by the vendor
Nylon 66 material, minimum 4 sq mm, screw type for control wiring and potential circuit.
7.2.7.1 Essential provision for CT terminals Sliding link type disconnecting terminal block screw driver operated stud type with facility for CT terminal shorting material of
___________________________________________________________________________________________ housing melamine/ Nylon66
7.2.8 Cable glands to be used by the vendor
Nickel plated brass double compression weatherproof cable gland
7.2.9 Cable lugs to be used by the vendor
7.2.9.1 For power cables Long barrel medium duty
Aluminum lug with knurling on inside surface
7.2.9.2 For Control Cable Tinned copper pre insulated Pin, Ring, Fork type as applicable 7.2.10 Painting of transformer, marshalling
box for CT, cable boxes etc.
7.2.10.1 Surface preparation By 7 tank pretreatment process or shot blasting method
7.2.10.2 Finish on internal surfaces of the transformer
Bright Yellow heat resistant and oil resistant paint two coats. Paint shall neither react nor dissolve in hot transformer insulating oil.
7.2.10.3 Finish on inner surface of the CT terminal box
White Poly urethane paint anti condensation type two coats , minimum dry film thickness 80 microns
7.2.10.4 Finish on outer surface of the transformer, CT terminal box, frame parts
Battle ship Grey shade 632 Poly urethane paint two coats , minimum dry film thickness 80 microns
7.3.0 Fittings & accessories
7.3.1 Rating and Diagram Plate Required
7.3.1.1 Material Anodized aluminum 16SWG
7.3.1.2 Background SATIN SILVER
7.3.1.3 Letters, diagram & border Black
7.3.1.4 Process Etching
7.3.1.5 Rating and Diagram Plate details
Following details shall be provided on rating and diagram plate as a minimum
i) type/kind of transformer with winding material, ii) standard to which it is manufactured
iii) manufacturer's name; iv) transformer serial number; v) month and year of manufacture vi) rated frequency in Hz
vii) rated voltages in kV viii) number of phases ix) rated power in kVA x) type of cooling (ONAN) xi) rated currents in A
xii) vector group connection symbol
xiii) 1.2/50 s wave impulse voltage withstand level in kV xiv) power frequency withstand voltage in kV
___________________________________________________________________________________________ principal, minimum and maximum tap
xvi) load loss at rated current;
xvii) no-load loss at rated voltage and frequency
xviii) continuous ambient temperature at which ratings apply in deg C xix) top oil and winding temperature rise at rated load in deg C;
xx) winding connection diagram with taps and table of tapping voltage, current and power
xxi) transport weight of transformer xxii) weight of core and windings xxiii) total weight
xxiv) volume of oil xxv) weight of oil
xxvi) name of the purchaser xxvii) PO no and date xxviii) Guarantee period
7.3.2 Terminal marking Plate for Bushing, anodized aluminum black lettering on satin silver background both inside cable boxes near termination and on cable box cover (all fixed by rivet)
Required
7.3.3 Company Monogram Plate fixed by rivet
Required 7.3.4 Lifting Lug to lift complete
transformer with oil
Required 7.3.5 Lifting lug for top cover Required
7.3.6 Lashing Lug Required
7.3.7 Jacking Pad with Haulage hole to raise or lower complete transformer with oil
Required
7.3.8 Detachable Bidirectional flat roller Assembly
Required 7.3.9 Pockets for ordinary thermometer on
tank cover with metallic identification plate fixed by rivet.
Required
7.3.10 Drain valve (gate valve) for the main tank with cork above ground by 150mm minimum with padlocking and valve guard with metallic identification plate fixed by rivet.
As per manufacturer design
7.3.11 Filter valve (gate valve) at top with padlocking and valve guard with metallic identification plate fixed by rivet.
As per manufacturer design
7.3.12 Air Release Plug on tank cover with metallic identification plate fixed by rivet.
As per manufacturer design
7.3.13 Oil level indicator As per manufacturer design 7.3.14 Earthing pad on tank for transformer
earthing complete with non ferrous
___________________________________________________________________________________________ nut bolt, washers, spring washers
etc. with metallic identification plate fixed by rivet
7.3.15 Rain hood for vertical gasket joints Desirable 7.3.16 Earthing bridge by copper strip
jumpers on all gasket joints at at least two points for electrical continuity
Required
7.3.17 Skid base welded type with haulage hole
Required 7.3.18 Core , Frame to tank Earthing Required 7.3.19 Danger plate made of Anodized
aluminum with white letters on red background on Transformer, cable boxes (all fixed by rivet)
Required
7.3.20 Caution plate for Off Circuit tap changer fixed by rivet.
Required 7.4.1 Pressure relief valve make Sukrut
7.4.2 CT make Pragati
7.4.3 Bushings make Baroda bushing / BSES approved
make.
8.0 Dry Type Distribution Transformer (400 / 630 / 1000 KVA) For dry type distribution transformer following design shall be complied. 8.1 Major Design criteria
8.1.1 Voltage variation on supply side + / - 10 % 8.1.2 Frequency variation on supply side +/ - 5 %
8.1.3 Transient condition - 20 % or + 10 % combined variation of voltage and frequency
8.1.4 Service Condition Refer Annexure B, the transformer is to be designed for PSS service condition as specified, but its full rating shall be available if located indoor in poorly ventilated atmosphere
8.1.5 Insulation level
8.1.5.1 One minute power frequency withstand voltage
3kv for 415v system & 28kv for 11kv system 8.1.5.2 Lightning impulse withstand
voltage
75kv peak for 11kv system 8.1.6 Short Circuit withstand level Refer Annexure B
8.1.6.1 Three phase dead short circuit at secondary terminal with rated voltage
___________________________________________________________________________________________ maintained on the other side
8.1.6.2 Single phase short circuit at secondary terminal with rated voltage maintained on other side
For 3 secs.
8.1.7 Overload capability As per IEC 60905
8.1.8 Noise level Shall not exceed limits as per NEMA TR-1 with all accessories running measured as per IEC 551 / NEMA standard
8.1.9 Radio Influence Voltage Maximum 250 Microvolt
8.1.10 Harmonic currents Transformer to be designed for suppression of 3rd, 5th, 7th harmonic voltages and high frequency disturbances.
8.1.11 Partial Discharges Transformer to be free from partial discharge upto 120 % of rated voltage as the voltage is reduced from 150 % of rated voltage i.e. there shall be no significant rise above background level
8.2 Major Parameters
8.2.1 Rating 400 KVA / 630 KVA / 1000 KVA
8.2.2 Voltage Ratio 11000 / 0.433 kV
8.2.3 Vector Group Dyn11
8.2.4 Reference design ambient temperature
40 deg C
8.2.5 Type Dry, core type, step down
8.2.6 Type of cooling AN
8.2.7 Reference Standard IS: 11171
8.2.8 No. of phases 3
8.2.9 No. of windings per phase 2 8.2.10 Rated frequency ( Hz ) 50 Hz 8.2.11 Highest system voltage HV side 12 kv 8.2.12 Highest system voltage LV side 460 volt 8.2.13 System earthing
8.2.13.1 HV Solidly earthed
8.2.13.1 LV Solidly earthed
8.2.14 Percentage Impedance at 130 deg. C
8.2.14.1 400 kVA 5 % with IS tolerance
___________________________________________________________________________________________
8.2.14.3 1000 kVA 5 % with IS tolerance
8.2.15 Maximum No load Loss in KW
8.2.15.1 400 kVA 0.90
8.2.15.2 630 kVA 1.2
8.2.15.3 1000 kVA 1.78
8.2.16 Max. full load losses at 130 deg. C, kW at principal tap
8.2.16.1 400 kVA 3.4
8.2.16.2 630 kVA 5.4
8.2.16.3 1000 kVA 7.5
8.2.17 Temperature Rise winding 90 Deg.C
8.2.18 Tap link current rating, Amp
8.2.18.1 400 / 630 kVA 60 A / 100A
8.2.18.2 1000kVA 125 A
8.2.19 Design Clearances 8.2.19.1 Clearances Phase to Phase
A For nominal system voltage of 11 kV 180 mm min. B For nominal system voltage of 415 V 25 mm min. 8.2.19.2 Clearances Phase to Earth
A For nominal system voltage of 11 kV 120 mm min. B For nominal system voltage of 415 V 25 mm min. 8.2.20 System Fault Level , HV side 350 MVA 8.2.21 System Fault Level , LV side 35 MVA
8.2.22 Loss capitalization formulae As per CBIP manual (see note 1) 8.2.22.1 No load Loss capitalization figure Rs. 235277 per kW
8.2.22.2 Load loss capitalization figure Rs. 131454 per kW 8.3 Construction & Design
8.3.1
Core
8.3.1.1 Material High grade , non ageing, low loss, high permeability, grain oriented, cold rolled silicon steel lamination
8.3.1.2 Grade Premium grade minimum M4 or better
8.3.1.3 Lamination thickness Maximum 0.27 mm 8.3.1.4 Design Flux Density at rated
conditions at principal tap
1.7 Tesla maximum allowed 8.3.1.5 Maximum Flux Density at 10 % over
excitation / over fluxing
___________________________________________________________________________________________ 8.3.1.6 Core Design Features i) All steel sections used for supporting
the core shall be thoroughly sand blasted after cutting , drilling, welding
ii) Provision of lifting lugs for core coil assembly
8.3.2 Winding
8.3.2.1 Material Electrolytic Copper
8.3.2.2 Maximum Current Density allowed Maximum allowed 3.0 A per sqmm. 8.3.2.3 Winding Insulating material Class F minimum, free from
compounds liable to ooze out, shrink or collapse. Uniform insulation shall be applied to the windings and overall winding shall be cast resin.
8.3.2.4 Tapping Off Circuit taps on HV winding , + / - 5 % in steps of 2.5 % , change of taps by link
8.3.2.5 Essential provision for tap links Shall be shrouded with cover made from insulating material. To prevent deposit of dust.
Tap link inspection transparent window shall not be provided on the HV side door
8.3.2.6 Design features i) Stacks of winding to receive adequate shrinkage treatment ii) Connections braced to withstand
shock during transport, switching, short circuit, or other transients. iii) Minimum out of balance force in the
transformer winding at all voltage ratios.
iv) Conductor width on edge
exceeding six times its thickness v) The termination bus-bar coming
out from winding shall be tinned Copper
vi) Transposed at sufficient intervals. vii) Threaded connection with locking
facility.
viii) Winding leads rigidly supported , using guide tubes if practicable ix) Provision of taps as indicated in the
technical particulars 8.3.2.7
Essential provision of HV and LV winding leads
Phase marking required near termination on both HV and LV side. Phase colour coding required on insulating sleeves on both HV and LV side.
Phase sequence 1U, 1V, 1W from left to right looking inside from the HV side door.
___________________________________________________________________________________________ right to left looking inside from LV side
door
Adequate HV termination clearance. Provisin of check nut in all HV and LV winding lead connection.
8.3.3
Vibration Isolator
Vibration isolation pads shall be installed between core and coil assembly and enclosure base
assembly to prevent the transmission of structure borne vibrations.
8.3.4 Bushings/Support Insulator/ terminations
8.3.4.1 Type of HV and LV Bushings, support insulators
Epoxy Resin Cast 8.3.4.2 Minimum Creepage of bushings and
support Insulators
25 mm / kV 8.3.4.3 Arcing horns Not required
8.3.4.4 Termination on HV side By cable within main enclosure 8.3.4.5 Support of HT cable within enclosure By MS flat of min size 50 x 6 mm 8.3.4.6 Termination on LV side By tinned copper busbar within main
enclosure 8.3.5 Hardware
8.3.5.1 External Stainless Steel only
8.3.5.2 Internal Cadmium plated except special hardware for frame parts and core assembly as per manufacturer’s design
8.3.6 Gasket Neoprene rubber based gasket.
8.3.7 Control cable specification (to be used by the vendor)
PVC insulated, extruded PVC inner sheathed, armoured, extruded PVC outer sheathed 1100 V grade control cable as per latest edition of IS 1554 part 1 minimum 2.5 sqmm for signals and 4 sqmm for CT with multistrand copper conductor
8.3.8 Specification of wires to be used inside WTI box etc.
PVC insulated multistrand flexible copper wires of minimum 2.5 sqmm size, 1100 V grade as per latest edition of relevant IS
8.3.9 Terminal Blocks to be used by the vendor
Nylon 66 material, minimum 4 sq mm, screw type for control wiring and potential circuit.
8.3.10 Labels and Name plate All name plate, wiring scheme plate, R&D plate , caution plate, danger plate,
___________________________________________________________________________________________ phase identification plate, identification
plate shall be aluminium with black engraving
Sticker of any form is not acceptable. 8.3.11 Fixing of name plate By riveting only at appropriate location.
8.3.12 Insulating support material for base plate for mounting components
Backelite shall not be used as a base plate for mounting any components, insulating material non hygroscopic insulating material like FRP shall be used.
8.4 Minimum Protective devices on
Transformer
8.4.1 Surge Arrestor Required, Connected on Transformer Primary side on all three phases
8.4.1.1 Type Gapless Metal oxide
8.4.1.2 Housing Polymeric preferable
8.4.1.3 System Voltage , kV rms 11
8.4.1.4 Rated Voltage of Arrestor, kV rms 9
8.4.1.5 Continuous operating voltage , kV rms
6.35
8.4.1.6 Maximum Continuous operating voltage, kV rms
7.65
8.4.1.7 Nominal Discharge Current, kA peak 5
8.4.1.8 Energy Absorption Capability, kJ/kV Greater than 2.5
8.4.1.9 Creepage factor 25 mm /kV
8.4.1.10 Reference std IS 3070 part 3 and IEC 99-4
8.4.2 Winding Temperature scanner Required
8.4.2.1 No of RTD inputs Five (Three for windings, one for enclosure & one shall be spare)
___________________________________________________________________________________________ RTD for enclosure temperature
monitoring shall be fixed at enclosure Top from inside to give max. enclosure temp reading & shall be wired upto temp. scanner to indicate the reading 8.4.2.2 Location of winding RTD At location of winding where maximum
temperature is expected. 8.4.2.3 No of potential free trip contacts Two
8.4.2.4 No of potential free Alarm contacts Two
8.4.2.5 Auxiliary supply 240 V AC, 1 phase, 50 Hz. Tapped from LV side busbar through a MCB located inside box
8.4.2.6 Winding Temperature Scanner terminal Box
Required
8.4.2.7 Size As per Manufacturer’s Standard 8.4.2.8 Fixing of instrument within box On base plate
8.4.2.9 Fixing of terminals within the box On C channel available with the terminals
8.4.2.10 Location Within enclosure frame such that box door comes in line with enclosure surface
8.4.2.11 Auxiliary Supply in box Tapped from main LV busbars, taken via MCB for isolation and protection of scanner, MCB to be fixed on DIN rail with clamps on two sides.
8.4.2.12 Essential provision Wiring diagram to be fixed on the back of door along with brief details of scanner, HV side , LV side door limit switches to be wired up-to Terminal Block, Service socket to be provided with switch, fuse and link.
8.5..0
Fitting and accessories
8.5.1 Rating & Diagram plate Required
8.5.1.1 Material Anodized aluminum 16SWG
8.5.1.2 Background SATIN SILVER
8.5.1.3 Letters, diagram & border Black
8.5.1.4 Process Etching
8.5.1.5 Name plate details Following details shall be provided on rating and diagram plate as a minimum
i) type of transformer i.e cast resin with winding material
ii) standard to which it is manufactured iii) manufacturer's name;
iv) transformer serial number; v) month and year of manufacture vi) rated frequency in Hz
vii) rated voltages in kV vii) number of phases
___________________________________________________________________________________________ viii) rated power in kVA
ix) type of cooling x) rated currents in A xi) vector group symbol
xii) 1.2/50 s wave impulse voltage withstand level in kV
xiii) power frequency withstand voltage in kV
xiv) impedance voltage at rated current and frequency in
percentage at principal, minimum and maximum tap at highest temperature
xv) load loss at rated current at highest temperature
xvi) no-load loss at rated voltage and frequency
xvii) auxiliary loss
xviii) continuous ambient temperature at which ratings apply in C xix) winding connection diagram with
taps and table of tapping voltage, current and power xx) transport weight of transformer xxi) weight of core and windings xxii) weight of enclosure and fittings xxiii) total weight
xxiv) tapping details xxv) phase CT details xxvi) Class of insulation xxvii) IP protection rating of the
enclosure
xxviii) name of the purchaser xxix) PO no and date xxx) Guarantee period 8.5.2.1 Detachable Bi-directional flat Roller
Assembly
Required
8.5.2.2 Essential provision Roller dia. 150 mm min., roller to be fixed in such a way so that the lowermost part of the skid is above ground by at least 100 mm when the transformer is installed on roller. 8.5.3 Earthing pad on enclosure for
transformer earthing complete with Stainless Steel nut, bolt, washers, spring washers etc.
Required with identification plate on outside of enclosure.
8.5.4 Core, Frame to tank Earthing Required 8.5.5 Off Circuit tapping link Required
8.5.6 Tap link position plate Required inside HV side door 8.5.7 Danger plate made of Anodized Required
___________________________________________________________________________________________ aluminum with white letters on red
background on HV and LV side
8.5.8 Skid with Haulage lugs Required 8.5.9 Lifting lugs for complete transformer Required 8.5.10 Caution Plate for tap links Required 8.5.11 Ventilation louvers with stainless steel
wire mesh and rain water guard
Required as per Manufacturer’s design, but it is to be provided minimum
required to prevent ingress of excessive dust.
8.5.12 Surge Arrestor & its Grounding bushing
Required
8.5.12.1 Essential provision Surge arrestor shall be erected vertically in such a way that the surge arrestor can be removed at site without removing HV cable lug.
Surge arrestor shall not be used for any kind of support.
Surge arrestor grounding strip to be routed to the surge arrester grounding bushing near bottom of enclosure with proper support.
Surge arrestor grounding bushing shall be identified by identification plate on outside of enclosure.
Surge arrestor grounding bushing shall be supplied with all hardware to readily connect purchaser’s ground lead. 8.5.13 LV neutral grounding provision Required, min. 20 nos
8.5.13.1 Essential provision LV neutral to be grounded at two different earth pit by 50X6mm GI strip. 8.5.14 Winding temperature scanner Required
8.5.15
RTD in Winding and near top of enclosure.
___________________________________________________________________________________________ 9.0 Low voltage Bus bar system
The equipment shall have all the following features -
9.1 LV bus bar From transformer LV bushing to ACB
and from ACB to MCCBs
9.2 Type of connection on transformer By flexible copper link rated 2000 / 1250 / 800 Amp for 1000KVA / 630 KVA / 400 KVA transformers.
Tinned copper busbar, size shall be as per manufacturer design. All the phases and neutral busbar shall be same rating / size.
9.3 Bus bar size for phase & neutral
Suitable spreader to be provided at outgoing side of MCCB to connect 300 sqmm cable through aluminum lug. 9.4 Bus bar support insulators 1 kv voltage class, SMC epoxy 9.5 Insulator creepage distance 25mm / kv
9.6 Bus bar sleeve insulation Color coded, for 1kv
9.7 Bus bar rated current Suitable for 2000A / 1250A / 800A continuous current rating within the 10K class enclosure @ 400 C ambient temp 9.8 Bus bar short circuit withstand 50 kA for 1 sec
9.9 Maximum temperature rise 20 deg C above ambient 40 deg C
10.0 Low voltage switchgear, ACB & MCCB. The equipment shall have all the following features -
10.1.0 Air Circuit Breaker (ACB) Fixed type 3 pole with fully isolable neutral link, one break per pole
10.1.1 ACB - On & OFF operation Manual as well as electrical by spring charged mechanism
10.1.2 ACB operating mechanism Trip free, anti pumping type 10.1.3 Spring charging method Manual as well as electric motor 10.1.4 Spring charging motor supply 1 ph 240v tapped from LV bus bar 10.1.5 Close & trip coil supply 1 ph 240v tapped from LV bus bar 10.1.6 ACB Neutral connection Fully isolable link sized for 2000 Amp
10.1.7 ACB rated voltage 415v +/- 10% at 50Hz
10.1.8 ACB rated current 2000 A / 1250 A / 800A continuous 10.1.9.1 ACB rated 3 phase short circuit
breaking capacity Ics = Icu
50kA minimum at 415v and 50Hz 10.1.9.2 ACB rated 3 phase short circuit
withstand capacity, Icw
50kA for 1sec 10.1.10 ACB SC making current capacity 100kA peak 10.1.11 ACB rated insulation level 1000volt 10.1.12 ACB mechanical & electrical
endurance
___________________________________________________________________________________________ 10.1.13 ACB utilization category as per IS B
10.1.14 ACB indications ON, OFF & TRIP
10.1.15 ACB operation - manual ON, OFF by push buttons 10.1.16 ACB operation - electrical ON, OFF by TNC switch 10.1.17 ACB overload, short circuit & earth
fault protection
By static or micro processor based releases
10.1.18 Approved make of ACB 10.2.0 MCCB
a) For 990/1000 KVA Outgoing feeders – 7 nos 400Amp APFC system – 1 no. 630 Amp b) For 630 KVA Outgoing feeders – 5 nos 400Amp
APFC system – 1 no. 400 Amp c) For 400 KVA Outgoing feeders – 5 nos 400Amp
APFC system – 1 no. 400 Amp
10.2.1 MCCB type 3 pole, one break per pole
10.2.2 MCCB - On & OFF operation Manual by handle
10.2.3 MCCB Neutral connection Fully isolable link sized for rated current
10.2.4 MCCB rated voltage 415v +/- 10% at 50Hz
10.2.5 MCCB rated continuous current 400 Amp 630 Amp 10.2.6 MCCB rated 3 phase short circuit
breaking capacity Ics = Icu
35kA minimum at 415v and 50Hz 10.2.7 MCCB rated 3 phase short circuit
withstand capacity, Icw
8kA for 1sec 10.2.8 MCCB SC making current capacity 75kA peak 10.2.9 MCCB rated insulation level 1000volt 10.2.10 MCCB mechanical & electrical
endurance
As per IS 13947 / IEC 10.2.11 MCCB category of duty B as per IS / IEC 947 10.2.12 MCCB indications ON, OFF & TRIP
10.2.13 MCCB protection Thermal magnetic release + earth fault By tinned Cu bar with double PVC insulation
10.2.14 Connection to ACB main bus
Size of busbar shall be as per manufacturer design.
10.2.15 Connection to outgoing cables By terminals suitable upto 4cx300sqmm AYFY 1100 volt grade cable
11.0 Automatic Power Factor Correction system
The APFC equipment shall be located in LV compartment of package enclosure and shall have all the following features -
11.1 APFC rating 300 KVAR / 200 KVAR
11.2 APFC mounting All components mounted in shelf type
arrangement on package substation enclosure LV compartment wall or RMU compartment wall
___________________________________________________________________________________________ 11.3 APFC relay & data logger Mounted on base plate supported on
compartment wall by three hinges 11.4 APFC system bus bar size 50x10mm tinned copper mounted on
SMC insulators 1100v grade
11.5 APFC system CT input signal From CT on transformer LV side by 7c2.5sqmm YY 1100v grade cable 11.6 APFC capacitor modules
a) For 300KVAR 6X50 KVAR three phase compensation b) For 200 KVAR 8X25 KVAR three phase compensation 11.7 Capacitor duty contactor for each
capacitor module
Utilization category 6b as per IS, make – ABB only
11.8 MCCB for each capacitor module 100 Amp, Three Pole, Ics=Icu=35kA 11.9 Connection to each MCCB from
APFC system bus
By 35sqmm copper wire double insulated with tinned copper lugs
11.10 APFC control supply Through 415/240v transformer, 2amp / 6amp SP MCB
11.11 APFC relay Microprocessor based relay for
automatic control of minimum 12 capacitors in sequential or cyclic switching fashion with settable time delay 0 -180 sec
11.12 APFC relay LCD display with self monitoring feature
To show no. of capacitors energized, actual PF & target PF, voltage & current
11.13 Target power factor setting range 0.8 lag to 0.9 lead in steps of 0.1
11.14 APFC relay sensing 3 phase CT input 5 amp to sense max load current
11.15 No volt protection in relay To switch OFF all capacitors
11.16 Capacitor unit 50KVAR type Double layer All Poly Propylene (APP) or Mixed Poly Propylene (MPP)
11.17 Capacitor unit construction 1.5mm thick sheet metal welded tank or Al cylindrical construction
11.18 Capacitor unit impregnant Dry type filler or non PCB liquid 11.19 Capacitor unit conducting layer Al foil or metalised film
11.20 Capacitor sealing Hermetic sealing after vacuum process 11.21 Capacitor unit safety Pressure sensitive dis connector or
internal fuse for each element
11.22 Discharge resistor Between all three phases of capacitor unit, to reduce the voltage across the capacitor to 50V or less in one minute 11.23 Terminal bushings For rated voltage class 1 KV
Suitable wires / terminals brought out from capacitor unit is also acceptable. 11.24 Earth connection for individual
capacitor container
To be done & connected to main earth bus bar of the panel
11.25 APFC Operational features
11.25.1 Automatic power factor correction To achieve target lagging power factor without hunting
___________________________________________________________________________________________ frequency (50 Hz)
11.25.3 Operation with over voltage 115% of rated voltage for 12 hours in a day
11.25.4 Operation with harmonic distortion THD voltage – 5% & THD current 3% 11.25.5 Maximum permissible over current 1.3 times rated current, continuous
11.25.6 Dielectric loss 0.2 watt per KVAR maximum
11.25.7 Temperature Category & Maximum temperature rise
- 5 / 60 deg C
Not exceeding 10 deg C over 60 deg C.
11.25.8 Residual voltage after
disconnection from mains
50 volts maximum after 60 seconds 11.25.9 Design life of capacitor unit Minimum 10 years
11.26.0 Data Logger (approved by requisite authority /
Electrical inspector)
11.26.1 Accuracy class 0.5, microprocessor based with LCD display, with 3 CTs for measurement of Kwh cumulative, power factor, voltage & current of transformer secondary, THD of voltage.
11.26.2 Data logging of Kwh value at every 30 minutes to give cumulative reading of Kwh for 45 days minimum, data downloadable in ASCII-II or MS Excel format
11.26.3 - Display of DATE, TIME, station ID
- Display & log power parameters phase wise & total ( load current, kVA, kW & PF).
- Display & log kVAr phase wise & total. - Display TDH V or current.
- The logger shall be with built in communication facility of RS485 / RS232 to down load all parameters on demand.
11.27 APFC approved make of components
11.27.1 Switch ABB / Siemens / L&T (Salzer)
11.27.2 HRC Fuse Links Alstom / Siemens / L&T / GE
11.27.3 Load manager L&T / Enercon / AE / DUCATI
Phasetrac M-40
11.27.4 APFC relay Beluk / ABB / Fraco / Ducati
11.27.5 AC Contactors ABB
11.27.6 Terminals Connectwell / Elmex
11.27.7 Push buttons / Actuator L&T / Teknic / Siemens
11.27.8 MCCB ABB / L&T / Siemens
11.27.9 Capacitor ABB / Universal / Shreem
12.0 Energy metering - LT
The equipment shall have all the following features -
12.1 Energy meter By Purchaser
12.2 Energy meter box To be provided mounted on enclosure wall in LV compartment
12.3 Energy meter box Size 650 mm height x 450 mm width x 275 mm depth.
___________________________________________________________________________________________ mm size,
channel shall be movable on vertical slotted angle 40 x 40 mm size at two ends
12.5 No of horizontal channels to be provided
Four 12.6 Fixing of terminal blocks within the
box
On horizontal slotted channel with the help of C channel available with the terminals
12.7 Box door design with antitheft hinge, padlock facility, door fixed by stainless steel Allen screw M6 size
12.8 Terminal strip As per Cl. 4.7 of the specs. 12.9 Cables and wires
PVC insulated, extruded PVC inner sheathed, armored, extruded PVC outer sheathed 1100 V grade control cable as per latest edition of IS 1554 part 1 minimum 2.5 sq mm for signals and 4 sq mm for CT with multi strand copper conductor.
12.10 Cable Glands Nickel plated brass double
compression weatherproof cable gland
12.11 Lugs on wires Tinned copper
12.12 Potential signal in CT box Tapped from main LV bus bar
12.13 Wiring diagram To be fixed on the back of door along with CT spec. on Aluminum engraved plate fixed by rivet.
13.0 Enclosure for packaged substation
The enclosure shall house all the components listed in clause 4.0 and shall have all the following features -
13.1 Service conditions For outdoor use as per Annexure B 13.2 Material for enclosure Galvanized sheet steel 2 mm thick
CRCA for all side doors, covers
13.3 Enclosure construction Frame supported construction with all doors, covers welded with steel channel ribs at every 1000mm minimum
13.4 Lifting lugs for site handling / lifting by crane
Four numbers on top to enable lifting of total package unit without any problem 13.5 Doors for RMU compartment & LV
compartment
With anti theft hinge minimum 3 nos., with lockable handle & with padlocking facility
13.6 Two side covers for transformer compartment
Bolted with Allen head type bolts to main frame
13.7 Top & other side walls of package substation enclosure
Welded sheet metal to main frame 13.8 Removable canopy above top cover Min. 2 mm thick galvanized sheet metal
with 10º slope
___________________________________________________________________________________________ total static and dynamic load
13.10 Base frame bottom support pads for fixing by bolt to foundation
Minimum six numbers to rest on foundation
13.11 Enclosure compartments Separate compartments for RMU, transformer & LV switchgear/APFC
13.12 Separation between RMU & transformer compartment
By sheet steel 2 mm thick 13.13 Separation between transformer
compartment & LV compartment
By sheet steel 2 mm thick IP53 for RMU compartment IP23 for transformer compartment 13.14 Degree of ingress protection
against solids & water as per
IS12063 IP33 for LV compartment
13.15 Louvers on side covers of transformer compartment & side walls of LV compartment
To be provided with steel wire mesh welded from inside so as to meet IP requirement as above
13.16 Louver area on cover / side wall 1500mm height x 1500mm desirable 13.17 Louver position from bottom level Minimum 200mm above bottom
13.18 Gland plate for RMU compartment 3 mm thick MS plate suitable for 3x3c300sqmm AYFY 11kv cable. Gland plate to be split type in two parts
13.20 Gland plate for LV compartment 3 mm thick MS plate suitable for 8 nos / 6 nos x4c300sqmm cable + 10x7c2.5sqmm cable. Gland plate to be split type.
13.21 Class of enclosure as per IEC 62271-202
10K 13.22 Limiting dimensions of package
enclosure
3800(L) x 2500(W) x 2500(H)
14.0 Earthing & Illumination
The enclosure shall have provision for earthing & illumination system as per following- 14.1.1 Earth bus connection brought out of
package substation enclosure to earth pad for connection to earth pit
Two earth pads for RMU, transformer & LV compartment each
Two earth pads for transformer neutral 14.1.2 Earth bus Material GI flat
14.1.3 Earth bus fault current capacity 26.3kA for 3 sec 14.1.4 Earth connection of all covers,
doors & structural parts to GI bus
By metallic jumper connection 14.1.5 Earth connection of RMU, ACB &
transformer body parts to GI bus
By two numbers of 50x6mm GI flat per equipment
14.1.6 Earth bus identification Shown by letter ‘E’ 14.2.1 RMU, transformer & LV
Compartment illumination
By 36w CFL fixture controlled through SPMCB & door limit switch
14.2.2 RMU, transformer & LV compartment power socket
5/15amp 3 pin socket controlled through 15 amp SPMCB
___________________________________________________________________________________________ 15.0 Labels & painting
The equipment shall have all the following features -
15.1 Name plate on package enclosure Fixing by rivet only
15.1.1 Material Anodized aluminum 16SWG / SS
15.1.2 Background SATIN SILVER
15.1.3 Letters, diagram & border Black
15.1.4 Process Etching
15.2 Name plate details Month & year of manufacture,
transformer rating, purchaser name & order number, guarantee period
15.3 Labels for meters & indications Anodized aluminum with white character on black background OR 3 ply Lamicoid
15.4 Danger plate on doors of RMU compartment & LV compartment
Anodized aluminum with white letters on red background
15.5 Enclosure painting surface
preparation
Shot blasting or chemical 7 tank process
Hot dip galvanizing – 80 micron thick 15.6 Enclosure painting external finish
Powder coated epoxy polyester base grade A, shade - RAL 7032, uniform thickness 60 micron minimum
15.7 Enclosure painting internal finish Powder coated epoxy polyester base grade A, shade - white, uniform thickness 80 micron minimum
15.8 BSES name plate At the center along the length “BSES” with anodized aluminum plate of size 14” approved by purchaser shall be fixed on PSS enclosure.
16.0 Approved make list of major equipments.
16.1 3 Way RMU ABB / Areva / CGL / Schneider /
Siemens
16.2 Oil type distribution transformer CGL / Kotsons / Areva / Kanohar / EMCO / Kirloskar / Voltamp or any other make approved by BSES.
16.3 Dry type distribution transformer Voltamp / Kirloskar or approved make of BSES.
16.4 ACB L&T / Schneider / ABB / GE / Siemens
16.5 MCCB L&T / GE / Schneider / ABB / Siemens
16.6 11KV cable Universal / KEI / Polycab / Hindusthan
___________________________________________________________________________________________ 17.0 Quality assurance by Vendor
17.1 Vendor quality plan To be submitted for purchaser approval for all components listed in clause 4.0 17.2 Inspection points
17.3 To be mutually identified & agreed in quality plan. List of all tests to be witnessed by Purchaser shall be given in Quality plan
18.0 Inspection & testing
One complete package unit shall be tested for type tests and every package unit shall be tested for temperature rise test. The testing of package units shall be as per
following -
18.1 Type test as per IS / IEC Equipment of type tested quality only to be offered. Type test conducted shall not be more than five years old.
18.2 Type test certificate to be submitted along with offer for 11kv RMU, 990KVA sealed type / dry type transformer, 2000amp ACB, 400amp & 630amp MCCB, 50KVAR capacitor. Transformer’s thermal & dynamic short circuit test report and chopped wave impulse test report to be submitted.
18.3 Following test shall be done on one unit in addition of test as per clause no.- 16.8
Functional test 18.4 On total package substation
assembly as per IEC62271-202 Temperature rise test
18.5 On 11kv RMU Breaker opening and closing time
measurement.
Temperature rise test Noise measurement test
Measurement of harmonic on no-load current.
Zero sequence impedance
Capacitance and dissipation factor between winding to earth and in between winding.
18.6 On 990KVA transformer
18.6 On ACB & MCCB Primary current injection test ( tripping and non tripping characteristic test) 18.8 Routine & acceptance test To be carried out as per IEC 62271-202
and approved QAP. 18.9 Right to waive off tests Reserved by Purchaser
19.0 Shipping, Handling and Site support
19.1 Packing for transportation Protection against rain, dampness, vibration required
19.2 Packing identification label To show purchaser name, address, purchase order number, equipment name, quantity.
___________________________________________________________________________________________ 19.3 Accessories & tools Packed in separate wooden case or box
20.0 Deviations
Deviations from this Specification shall be stated in writing with the tender by reference to the Specification clause / GTP/ Drawing and a description of the alternative offer. In absence of such a statement, requirements of the Specification shall be met without exception.
___________________________________________________________________________________________ Annexure - A Scope of supply
1.0 The scope of supply shall include following
1.1 Design, manufacture, testing at manufacturer works before dispatch, packing, delivery and submission of all documentation of Packaged substation with all accessories as per specification and supply of commissioning spares.
1.2 Packaged substation as per as per technical specification & GTP 1.3 Supervision of testing & commissioning of Packaged substation at site 1.4 BOQ as following - Sr No Purchaser Equipment Tag No / SAP code Location / Substation name Unit Quantity 1
2 e.g. Alaknanda No e.g. 1
3
2.0 Submission of documents
2.1 Submission with Bid (2 hard copies + 2 soft copy in CD format)
i. GA drawing (Complete assemble, RMU, transformer, LT panel + other items) ii. BOM of Packaged substation
iii. Quality plan for Packaged substation
iv. Type test reports of identical type of Packaged substation components v. Guaranteed technical particulars of Packaged substation
vi. Calculation for sizing of Transformer
vii. Catalogues & manuals for RMU + Transformer + LT switchgear items + APFC + Energy meter
2.2 Submission after award for approval (2 hard copies + 2 soft copy in CD format ) i. GA drawing (as above)
ii. BOM of Packaged substation iii. Quality plan Packaged substation iv. GTP of Packaged substation
___________________________________________________________________________________________ v. Installation, commissioning manual for all items in Packaged substation. (for
information)
vi. Operation & maintenance manual for all items in Packaged substation. (for information)
2.3 Submission of final approved documents (2 hard copies + 2 soft copies in CD format )
All above documents as per clause 2.2 above
3.0 Delivery schedule
3.1 Delivery period start date - from date of purchase order 3.2 Delivery period end date - as agreed with supplier 3.3 Material dispatch clearance - after inspection by purchaser
